Superconducting filter device

Abstract

A superconducting filter device is disclosed that includes a dielectric base substrate; a patch-type resonator pattern formed of a superconducting material on the base substrate; and a feeder extending in the vicinity of the resonator pattern. The feeder includes a transmission line part for signal inputting or signal outputting, the transmission line part extending toward the resonator pattern; a facing part bent from the transmission line part to face the resonator pattern; and an end part bent from the facing part in a direction away from the resonator pattern.

1 . A superconducting filter device, comprising:
 a dielectric base substrate;   a patch-type resonator pattern formed of a superconducting material on the base substrate; and   a feeder extending in a vicinity of the resonator pattern,   wherein the feeder includes   a transmission line part for one of signal inputting and signal outputting, the transmission line part extending toward the resonator pattern;   a facing part bent from the transmission line part to face the resonator pattern; and   an end part bent from the facing part in a direction away from the resonator pattern.   
   
   
       2 . The superconducting filter device as claimed in  claim 1 , wherein the feeder comprises a pair of feeders for the signal inputting and the signal outputting, and the paired feeders are arranged in line symmetry with respect to the resonator pattern. 
   
   
       3 . The superconducting filter device as claimed in  claim 1 , wherein the facing part has a line width greater than a line width of the transmission line part in the feeder. 
   
   
       4 . The superconducting filter device as claimed in  claim 1 , wherein La+Lb=λ/4 holds in the feeder, where La is a length of the end part, Lb is a length of the facing part, and λ is an effective wavelength. 
   
   
       5 . The superconducting filter device as claimed in  claim 4 , wherein 0.2≦(La/Lb)≦0.9 holds in the feeder. 
   
   
       6 . The superconducting filter device as claimed in  claim 1 , wherein W 1 <W 3 <W 2  holds in the feeder, where W 1  is a line width of the transmission line part, W 2  is a line width of the facing part, and W 3  is a line width of the end part. 
   
   
       7 . The superconducting filter device as claimed in  claim 1 , further comprising:
 an additional resonator pattern placed adjacently to the resonator pattern on the dielectric base substrate; and   an additional feeder paired with the feeder, the additional feeder extending in a vicinity of the additional resonator pattern,   wherein the paired feeders are arranged in one of point symmetry and rotational symmetry with respect to the two resonator patterns.   
   
   
       8 . The superconducting filter device as claimed in  claim 1 , wherein the feeder is a pattern having an angular C-letter shape. 
   
   
       9 . The superconducting filter device as claimed in  claim 1 , wherein the feeder has one of a microstrip-type structure and a triplate-type structure. 
   
   
       10 . The superconducting filter device as claimed in  claim 1 , wherein the feeder comprises one of a superconducting material and a metal material.